@SubRosa - I admit it that it was the captive that killed all the muties with some kung-fu moves, I just took the screenie at a perfect moment as the captive killed the last mutie to make it look like Logan did it.

Not even Logan knew what he was shooting at, but based on sounds he assumed it was a Super Mutant.

Surprisingly, water in that lake was not very irradiated. I'd think that being as close to the Glowing Sea would make it rad full, but in fact some water bodies far away from the Glowing Sea are way more irradiated.